Objectives. The aim of this study was to evaluate the occluding effect of dentinal tubule and sustaining power with dentifrice
nano-carbonate apatite in vitro.
Methods. In the first test, fifty dentin specimens were divided randomly into the following five groups; control group (baseline),
experimental group (20% n-CAp), negative control group (0% n-CAp), and positive control groups (1: 10% SrCl2 and 2: Er:Cr:YSGG
laser). The specimens of each group were brushed for 50 strokes with a V8 Cross Brushing Machine or laser irradiation for 90
seconds. In the second test, the dentin specimens of four groups except the control group were immersed in demineralization solution
(pH 4.8) for 3, 5, and 10 min after the first test. All the specimens were evaluated by SEM and quantified using an image analyzer.
The results were analyzed by one-way ANOVA and Tukey’s post hoc analysis using the SPSS 12.0 statistical package program.
Results. The 20% n-CAp group showed an occluding rate of 78% and significantly higher occlusion effects than the 0% n-CAp
group, 10% SrCl2 group and Er:Cr:YSGG laser group (p＜0.05). When immersed in acid solution for 3 min, the size of the dentinal
tubule not almost increased (ED Highlight - meaning is completely unclear) in 20% n-CAp group and Er:Cr:YSGG group. These
groups showed significantly higher sustaining power than the 0% n-CAp group (p＜0.05). However, there was a no significant
difference in immersion time for 5 and 10 min.
Conclusions. The dentifrice containing 20% n-CAp was the most effective in occluding the dentinal tubules and showed superior
sustaining power in the short-term